Influence of Different Surface Conditioning Methods on Adhesion of Resin Cement to Zirconia

Statement of the problem: The challenge of enhancing the bond between zirconia and resin remains, and the efforts continue to determine a simple method for achieving a durable bond. Objective: This study aimed to evaluate the effect of different surface conditioning strategies on the bond strength between zirconia and resin ce-ment. Materials & Methods: Forty zirconia specimens (Lava Plus) were fabricated and divided into four groups: control (no surface treatment), pri-mer application (Z-Prime Plus), experimental acid (H2O:HF:H2O2) applica-tion, and the combination of the acid and primer application (n=10). A dual-cure resin cement (RelyX Ultimate) was applied over the zirconia specimens. Shear bond strength tests were conducted using a universal testing machine with a cross-head speed of 1 mm/min. The results were analyzed using one-way ANOVA followed by Tukey's post hoc test within the 95% confidence interval. Results: The results of the one-way ANOVA showed that acid appli-cation alone (22.99 ± 2.49 MPa) and acid and primer application (25.24 ± 3.19 MPa) had significantly higher bond strength than the primer (18.87 ± 3.13 MPa) and control (14.91 ± 3.72 MPa) groups (P<0.05). However, there was no significant difference between the acid group and acid and primer combination group (P=0.396). The control group had the lowest bond strength in all test groups (P<0.05). Conclusions: Experimental acid treatment alone or in combination with primer application could be effective in improving the bond strength.